Background: The Joint Position Reproduction (JPR) approach has been commonly used to assess joint position sense (JPS), however, no prior study investigated its psychometric properties in children. This study aimed to assess the reliability and precision of a newly developed multi–joint JPR protocol for assessing lower limb JPS in school-aged typically developing (TD) children. Methods: Ankle, knee and hip JPS was assessed in TD children (aged 5–12 years), on two different days, by a single rater using a standardized JPR protocol (re–identification of a passively placed target position of the ipsilateral joint). The mean and best error(JRE,°) between target and reproduction angle were calculated from three–dimensional(3D) kinematics for each tested joint on both sides for three trials. Furthermore, total, joint– and limb–JRE scores were provided for clinical use. For JPR–reliability, the Intraclass Correlation Coefficient(ICC,2.1) was reported. For JPR–precision, the standard error of measurement (SEM) was calculated. Results: 270 JPR trials were assessed in 15 TD children (8.6±1.2 years,8boys). The mean and best JRE, summarized for all joints for test and retest, was 3.7° and 2.5°, respectively. The ICC were poor to fair(0.01–0.44) for mean JRE, but fair to very good(0.46–0.77) for best JRE. The SEM ranged from 0.8°–1.8°, depending on the joint and side being tested. Conclusion: Evaluating ankle, knee and hip JPS in children, using passive JPR, is more reliable and precise when using the best JRE. This study highlights the need for a multi–joint JPR approach in research and clinics, and provides joint- and limb-specific SEM values. Keywords: Assessment; Proprioception; Joint Position Sense; Reliability; Precision

The authors have declared no competing interest.

This study was supported by the Research Foundation Flanders (FWO) (grant number: 92836, 2021) and the Special Research Fund (BOF) for Small Research Project at Hasselt University (BOF19KP08)

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The Committee for Medical Ethics (CME) of Antwerp University Hospital (UZA)/ University of Antwerp (UAntwerpen), CME of Hasselt University (UHasselt) and the Ethics Committee Research of University Hospital of Leuven (UZ Leuven)/ University of Leuven (KU Leuven) gave ethical approval for this work (B3002021000145).

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